arXiv subjects

Robert L. Gluckstern

Publications and source records attributed to Robert L. Gluckstern.

3 recordsLinked to original sources

arXiv1997

Stability and Halo Formation in Axisymmetric Intense Beams

Beam stability and halo formation in high-intensity axisymmetric 2D beams in a uniform focusing channel are analyzed using particle-in-cell simulations. The tune depression - mismatch space is explored for the uniform (KV) distribution of the particle transverse-phase-space density, as well as for more realistic ones (in particular, the water-bag distribution), to determine the stability limits and halo parameters. The numerical results show an agreement with predictions of the analytical model for halo formation (R.L. Gluckstern, Phys. Rev. Letters, 73 (1994) 1247).

physics.acc-ph↗

arXiv1996

Coupling Impedances of Azimuthally Symmetric Obstacles of Semi-Elliptical Shape in a Beam Pipe

The beam coupling impedances of small axisymmetric obstacles having a semi-elliptical cross section along the beam in the vacuum chamber of an accelerator are calculated at frequencies for which the wavelength is large compared to a typical size of the obstacle. Analytical results are obtained for both the irises and the cavities with such a shape which allow simple estimates of their broad-band impedances.

acc-phys↗

arXiv1995

A General Approach for Calculating Coupling Impedances of Small Discontinuities

A general theory of the beam interaction with small discontinuities of the vacuum chamber is developed taking into account the reaction of radiated waves back on the discontinuity. The reactive impedance calculated earlier is reproduced as the first order, and the resistive one as the second order of a perturbation theory based on this general approach. The theory also gives, in a very natural way, the results for the trapped modes due to small discontinuities obtained earlier by a different method.

acc-phys↗